Mini-Excavator questions???

Rowski · Jun 11, 2005

I have some questions regarding mini excavators. This summer I had a few jobs that required more than just my backhoe on my tractor. So I rented 2 different excavators. After using both I have some questions. I'm not looking for right or wrong answers just your personal opinions.

Let me give you some more info on the conditions and machines used. One job needed some stone work (removing vegetation and arranging the rock wall {loosely stacked}). Removing old trees that were cut by some else 3 or 4 years ago (into a pile to burn at a later time). Then some stumping and smoothing out (pasture quality). The soil was wet (poor drainage due to clay under grass) and the grade was flat. For this job I used a Kubota KX121-3 with angle blade, steel tracks, 3ft (I think) digging bucket, hydraulic thumb, non cab model. The machine had about 650 hours on it and was maybe a year or two old. I put about 8 hours on the machine.

The next job I rented a John Deere 35c with rubber tracks, 26ish inch digging bucket, hydraulic thumb, non cab model. This job required stumping (5 year ols stumps), root removal of berry bushes and saplings (area was cut last year), lots and lots of grading (with blade). The soil is sandy with some stones, drains very very well. Put about 20 hrs on this machine.

My thoughts on the two machines.

KX121-3

Bigger machine, visibility not that good (right side and rear), bucket was to big for my situation, steel track gave a really rough ride, thumb design is nice (its a OEM thumb), seemed like it lacked a little power but that could be due to the bucket size, angle blade did not really do any thing for me.

JD 35c

Small looking machine but very powerful, rubber tracks give nicer ride and seems to have better traction, visibility is awesome, pretty tippy over the tracks, motion alarm very annoying, thumb design stinks (OEM thumb doesn't grab very well), the controls seemed to work easier than the KX212-3.

In my limited time of use on these machines are my thoughts in the general direction or out to lunch.

Are there other benefits to a ZTS machine other than visibility and getting into tighter spots??

In general, are rubber tracks better than steel??

What's up with the angle blade??

What manufacturer and model do you like and why??

BTW, the KX121-3 broke the bucket/thumb pivot pint after finishing the first job. I had to return it, they didn't have a pin in stock (the rental yard is a Kubota dealer). They did mention that they had several break. Possible problem?? That's why I ended up with a JD 35C, different rental yard.

I may be renting an excavator a few more time this summer. I'm trying to establish a good relationship with the rental yard. Most rental yards are good around here, just need to find a good machine.

Thanks for you help /forums/images/graemlins/smile.gif!!

JoshJ · Jun 12, 2005

( Are there other benefits to a ZTS machine other than visibility and getting into tighter spots?? )
If you are referring to Zero Tail Swing, then simply the fact that I wouldn't have to worry about it hitting something (one more thing to think about) would be worth it to me.

( In general, are rubber tracks better than steel??)
I havent run an excator (any size) but as far as I know rubber tracks are used for pavement/concrete, as they dont tear it up. The ride is also softer, but they dont last as long, and I think they are more expensive

( What's up with the angle blade?? )
....beats me /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif ummm, not real sure what you mean here. As far as a use, you drop it to gain leverage when digging over the front, and can use it to push dirt around (to some extent). If it angles side to side, you can move dirt faster that way (most of the time), but not spread it as nicely.

( What manufacturer and model do you like and why?? )
Sorry friend, but my advice on this one would be as good as flipping a coin. /forums/images/graemlins/crazy.gif I'm sure others can help you though.

nobull1 · Jun 12, 2005

I own a kx91-3 Kubota excavator c/w steel tracks. Previous to that I had a 035 Daewoo c/w steel tracks. To start with I hate the rubber tracks and would not buy another machine with them. When I purchased my KX91-3 it came with rubber and took months to get the steel. So I was forced to use the rubber in the mean time. Well after using steel for 5 years and then using rubber I found the only benefits to be quiet, easier on asphalt and concrete. The downfall is durability sucks. The potential for cutting and tearing is way too high for my liking. After a 100 hours on my new machine I was wondering if they would last another 100. This is with me the only operator and trying to be careful so I could sell them when the steel came in. In the end Kubota gave me a new set n/c which I will sell to the first person who asks and gives the right price. If you rent a machine and tear one I wonder who will foot the couple thousand bill to replace /forums/images/graemlins/smirk.gif As far as traction is concerned there is no comparison to steel. The first day I used the rubber tracks I was disappointed at the lack of traction and how easily they slipped. If there was a sharp rock under the track when it spins you know what will happen. The amount of weight you can push is at least 50% more with steel. The chances of a root or sharp rock ruining your day are just too great IMO. As far as how quiet the tracks are, the rubber are a lot quieter. To me how quiet or rough the tracks are means nothing compared to durability,workability of the machine. I always have my Peltor work tunes cranked so it doesn't matter anyways /forums/images/graemlins/cool.gif
The angle blade is something I don't have but would have it in a instant if it was available when I bought my machine. I would think it should cut your grading time down by a third.
The size of the bucket is a little too big for digging in my opinion for a 121. I would think it should have been a 24-28 digging bucket with a three foot ditching bucket.
The o turn excavators are a good thing as it is one less thing to worry about. The problems are in some cases 1) cab is too small due too making it a 0 turn 2) A lot of times they just widen the track stance to accomplish 0 turn(which means more room needed in width at job site) 3) The main one, tip ability due to the counter weight not being as far rearward as a non 0 turn. I find them to be a lot more unstable on rough terrain when reaching far off the sides or front/back. All that said I might still buy one if the time and price was right. Here is a link to my story about the KX91-3 that I purchased last year KX91-3

toy1 · Jun 13, 2005

Kx121-3 I can tell you from experience that it is a excellent machine. I would stay away from rubber track. they do not last long and I think they do more damage on sod then steel track. The angle blade was put on to allow for trench backfilling. I know own a 161 with angle blade and it works quite effectively. also a 161 or 121 are not ZTR.

nobull1 · Jun 13, 2005

Toy1,
Like minds on the rubber tracks /forums/images/graemlins/smile.gif. The rubber do seem to do more damage to sod than steel. IMO the rubber is way overrated. The maintenance cost per hour for rubber tracks is probably 3-5 dollars more per hour than steel. Funny how the public was sold on rubber tracks. The MFG's can make a lot more selling replacement rubber tracks than steel /forums/images/graemlins/smirk.gif.

coopers · Jun 14, 2005

I agree with what others are saying. The rubber tracks do seem to cause more damage than the steel tracks. Not sure if you actually did use a 3 foot digging but they should come in 1 foot trenching, 2 foot digging and a 3 foot smooth clean out bucket. I have had zero complaints on the performance of a 121-3. They are a well built machine, especially the newer models (04-05 or at least the 05's) and are a powerful machine. I do agree that the visibility of the machine's back right side are poor but you get used to it and know how close you are once you've used it enough. I'm not too familiar with the thumbs on our Kubota's, I believe they are kubota's own design or something like that. But they have more curve to them for logs and such than JD's.

Blake
WA

Rowski · Jun 14, 2005

Thanks for all the replies!!

I used the 35C some more this weekend and yesterday. My week rental is up on Wednesday.

I did notice that the 121-3, steel tracks, (a heavier machine than the 35C) did not tear grass and mark up dirt driveways as much as the rubber tracks. I also got into some moist clay on a slight hill and the rubber tracks did spin some.

I must say you guys got me very paranoid about the rubber tracks breaking. Yesterday day I had to stump 3/4 acre of smaller (1 to 3 inch stumps). I was so worried that I would tear a track. I have always been careful to not to drive where I haven't check (using bucket and blade) for stumps. Also don't do any "power turns" in rough ground. As per the rental policy of the 35C no damage wavier charge I'm responsible for damage other than wear.

So, what breaks a steel track?? Do steel tracks come off easier than rubber??

Thanks again /forums/images/graemlins/smile.gif!

nobull1 · Jun 14, 2005

What breaks a steel track? Well that's a good question /forums/images/graemlins/confused.gif. Don't recall ever hearing about steel tracks on a mini breaking. The wear part on the mini tracks is the pins and bushings. After a fair amount of use (approx. 2500 hrs give or take a thousand) all parts start to wear idlers, sprockets, pins bushings and rollers. When all these parts start to wear it will allow the track to come off a lot easier. I will say though on my Daewoo with steel tracks I had 2 teeth broken off the drive sprockets(don't know when or if I did it). This did not affect the performance at all. I suspect maybe a rock or a piece of rebar might have gotten jammed between the track and sprocket. If this was the case it is a good thing that they were steel tracks or it probably would have torn a cleat out of the rubber track /forums/images/graemlins/smirk.gif. Working around stumps you are right to be nervous about rubber tracks. This isn't rocket science just common sense once you know. I found it almost impossible to do a good job working around stumps with rubber tracks. They spin a lot easier and there is a lot of unknown beneath the tracks to make you think about cutting or ripping them. This all slows down the job. The rubber is great for the landscaper that has no stumps or slate/shale, sharp rocks or possible hidden treasures and has to cross asphalt or concrete all the time. I have 4 pieces of used conveyor belting 12" wide by 10' long. The times I have to go over asphalt/concrete I just put the belting down. This way no worry about tearing, cutting etc etc. and more traction to push, less damage to lawns and more control on slippery conditions. It's a no brainer to me, but some say I have no brain /forums/images/graemlins/blush.gif

coopers · Jun 26, 2005

Oh every once in a while a steel track will come off. We've had to send mechanics out to put 120 excavator tracks back on because they popped off. Not easy by any means and it takes a LONG time to get them back on. If the tracks are too tight or too loose they come off easier.

Blake
WA

nobull1 · Jun 26, 2005

I only had one track come off on me in the last five years. When I tried to reinstall the track there was no way to get it on even after taking the pressure off the idler. After like 4 hours or so I finally realized that I didn't have the grease pressure on the idler released as I thought I did /forums/images/graemlins/blush.gif /forums/images/graemlins/mad.gif. Once I found my mistake it took about 20 mins to put on. How hard to install will depend on where the machine is when it comes off IMO. This reminds me though of why it came off. There was three reasons 1) tracks were a little loose 2) was travelling in 4-6" rocks 3) was driving back wards with the idlers in the back. When the idlers are in the back and you are on uneven terrain you can roll the track off the idler. Normally the sprocket is in the back and it is near impossible to wind it off the sprocket. The idler is smooth and the right amount of pressure on the track at the right time makes it easy to roll off. My experience has been if in rough rocky ground be careful when in reverse with steel or rubber tracks and make sure you have the proper tension on the track.

deansdad · Jul 7, 2005

apologize for the late reply, but you've received a bunch of good responses to date. I (we, our small company) was one of the very early adoptors of the "mini" excavators...back in the days when they were looked upon as "toys" by the "real" excavator operators.
That most of those naysayers are now users, is just "come-up-enz" <g>.
Anyway....I can't agree more with those that are advising that rubber tracks should only be considered if your primary (and ONLY) consideration is minimizing damage to paved surfaces (for some operators, in some circumstances, that consideration is primary and the customer is willing to pay the freight)....other than that - rubber is a losing proposition for all the reasons that have been previously stated.
Vis-a-vis the "throwing steel tacks" issue....I'd come down on the side of yes, it CAN happen....but.....99% of the time it's either operator error or lack of preventive maintenance....the other 1% (or, maybe it's 5%, 10%) it's just "being in the wrong place at the wrong time...it CAN happen, sometimes....cost of doing business..........but, overall, it's a drop in the bucket compared to longevity costs of rubber.
Same logic works with ground damage...as others have so eloquently stated.....all else being equal (ground conditions, etc), a competent operator will cause less damage with steel tracks in almost every case (except pavement).
Re the "angled blade", I can't comment analytically since our Kubota mini (sorry, don't remember the exact mod #) was pre-angle blade days...but did have a straight blade.
What I can comment on is how often I said to myself...."...jeez, why didn't they put a put a tilt cylinder on here?".....a mini without a blade is, in MNSHO, a waste.......a blade on a mini without tilt even more so.
Mini Ex's, in the right situation, and beyond the macho attitudes of the "bigger is always better" crowd - are amazing machines....add a tilt blade, steel tracks (wide tracks if the situation dictates) and you've got a machine that can go in (through a small gate), get the job done, AND leave a mighty small footprint.........
......that might just be the reason you're seeing more and more of the "naysayers" of a few years ago, now sending out those 35 ton goosenecks with only a "mini" with their name on the side, onboard

nobull1 · Jul 7, 2005

Wecome Deansdad glad to see another excavator owner on board. I look forward to your point of view on construction/all topics.

Rowski · Jul 16, 2005

I ended up renting the KX121-3 with steel tracks again. I have used it about 25 hrs mostly stumping and rough grading. I must say the steel tracks are a great peice of mind. I don't have to worry about what I'm driving over. They are a bit noisy and rough but well work the piece of mind. Just wish the rental company had a cab with a/c for rent /forums/images/graemlins/frown.gif.

Thanks again.

Taylortractornut · Jan 7, 2006

Nobull, On your excavator do you have a top roller or does it have the slide bar since it came with rubber tracks. My Grey Market PC 50 uuKomatsu. Its a 13000 pound excavator. It has rubber and the top slide bar instead of a roller. I need some tracks as Ive already had a lug pull out of the track. I put a bolt through the cleat bar and the lug on the track. I can get a set of steel tracks rails,pads and bolts for 3800 from Komatsu . My Grey dealer can get rubbers for 3600. Ive gt a friend with the same machine but he left the slide bar on it. I dont like it as it has worn down the bushing alot more than the sprocket. I may get a pair of smaller Berco rollers to mount on the top. SOme of the older pc 50's came like this.

nobull1 · Jan 7, 2006

On my excavator there is three of 040 on the bottom and one 120 on the top. Don't know if you can tell but the bottom ones have a lip on each side and the top one is flat.

nobull1 · Jan 7, 2006

When I switched from rubber to steel all they had to do was add two of #090 and 110 to each side just as wear plates and guides. The only other thing that was done was to release a bit of pressure on the spring on the idlers.

Dirthog · Jan 8, 2006

sorry to argue but I have had rubber tracks on two different mini's both kobelco in the last 7 years yes I did have to replace a set of rubber track at around 2800hr. That being said no I would not take it into my stone pit to work or some other places but much better on pavement or even most dirt. Not mud though everything is a trade off. As far as cost to replace rubber and steel are about the same price. I know I have worked for a dealer for the last 33 years

Taylortractornut · Jan 8, 2006

Ive been an operator and mechanic for a few years myself I like the steel tracks in the part where at 2800 hours I can have the pins and bushings turned. I work alot in loose sand and in alot of rubble and sharp washed gravel at the lake. Im gonna get the clip on trackpad cavers with mine. I have a good friend with a 307 on steel with the neoprene ronded pads He does alot of golfcourse work and just slides on the stuff in a turn.

nobull1 · Jan 8, 2006

No argument needed Dirthog /forums/images/graemlins/smile.gif I only express my opinion and experience and would not argue about your results. I know a few people in the rental business as well as the construction industry and there is honestly a mixed opinion. A lot of people like them, and a lot hate them. Bottom line to me is steel "usually" doesn't have issues till you have at least a couple thousand hours. The rubber tracks just take one slip on the wrong surface and couple thousand gone. The steel in my opinion can take a little more use/abuse with out the potential cost of replacement. In my case I do some woods work as well as rocky surfaces and could not afford to take the chance. Anyhow look forward to your opinions, as 33 years working for a dealer is a wealth of knowledge. There isn't a lot of people with your experience that post here so try to post more often /forums/images/graemlins/smile.gif

nobull1 · Jan 8, 2006

( Im gonna get the clip on trackpad cavers with mine. I have a good friend with a 307 on steel with the neoprene ronded pads He does alot of golfcourse work and just slides on the stuff in a turn. )

I am curious about the trackpads covers. I haven't seen them locally and wondered what they were worth and type required. My thought would be they would be smooth on grass but would slide pretty easy on wet surfaces?